Otospondylomegaepiphyseal dysplasia (OSMED) is an autosomal recessive disorder of bone growth that results in skeletal abnormalities, severe hearing loss, and distinctive facial features. The name of the condition indicates that it affects hearing (oto-) and the bones of the spine (spondylo-), and enlarges the ends of bones (megaepiphyses).
Achondrogenesis type 1B is a severe autosomal recessive skeletal disorder, invariably fatal in the perinatal period. It is distinguished by its elongated, spherical midsection, small chest, and exceedingly short limbs. The feet can turn inward and upward (clubfeet), and the fingers and toes are little. Babies affected often have a soft out-pouching at the groin or around the belly button.
Cartilage–hair hypoplasia (CHH) is a rare genetic disorder. Symptoms may include short-limbed dwarfism due to skeletal dysplasia, variable level of immunodeficiency, and predisposition to cancer. It was first reported by Victor McKusick in 1965.
Collagen, type II, alpha 1 , also known as COL2A1, is a human gene that provides instructions for the production of the pro-alpha1(II) chain of type II collagen.
McCune–Albright syndrome is a complex genetic disorder affecting the bone, skin and endocrine systems. It is a mosaic disease arising from somatic activating mutations in GNAS, which encodes the alpha-subunit of the Gs heterotrimeric G protein.
Collagen alpha-2(XI) chain is a protein that in humans is encoded by the COL11A2 gene.
Autosomal recessive multiple epiphyseal dysplasia (ARMED), also called epiphyseal dysplasia, multiple, 4 (EDM4), multiple epiphyseal dysplasia with clubfoot or –with bilayered patellae, is an autosomal recessive congenital disorder affecting cartilage and bone development. The disorder has relatively mild signs and symptoms, including joint pain, scoliosis, and malformations of the hands, feet, and knees.
An osteochondrodysplasia, or skeletal dysplasia, is a disorder of the development of bone and cartilage. Osteochondrodysplasias are rare diseases. About 1 in 5,000 babies are born with some type of skeletal dysplasia. Nonetheless, if taken collectively, genetic skeletal dysplasias or osteochondrodysplasias comprise a recognizable group of genetically determined disorders with generalized skeletal affection. These disorders lead to disproportionate short stature and bone abnormalities, particularly in the arms, legs, and spine. Skeletal dysplasia can result in marked functional limitation and even mortality.
Multiple epiphyseal dysplasia (MED), also known as Fairbank's disease, is a rare genetic disorder that affects the growing ends of bones. Long bones normally elongate by expansion of cartilage in the growth plate near their ends. As it expands outward from the growth plate, the cartilage mineralizes and hardens to become bone (ossification). In MED, this process is defective.
Campomelic dysplasia (CMD) is a genetic disorder characterized by bowing of the long bones and many other skeletal and extraskeletal features. It can be lethal in the neonatal period due to respiratory insufficiency, but the severity of the disease is variable, and a significant proportion of patients survive into adulthood. The name is derived from the Greek roots campo, meaning bent, and melia, meaning limb. An unusual aspect of the disease is that up to two-thirds of affected 46,XY genotypic males display a range of disorders of sexual development (DSD) and genital ambiguities or may even develop as normal phenotypic females as in complete 46 XY sex reversal. An atypical form of the disease with absence of bowed limbs is called, prosaically, acampomelic campomelic dysplasia (ACD) and is found in about 10% of patients, particularly those surviving the neonatal period.
The sulfate transporter is a solute carrier family protein that in humans is encoded by the SLC26A2 gene. SLC26A2 is also called the diastrophic dysplasia sulfate transporter (DTDST), and was first described by Hästbacka et al. in 1994. A defect in sulfate activation described by Superti-Furga in achondrogenesis type 1B was subsequently also found to be caused by genetic variants in the sulfate transporter gene. This sulfate (SO42−) transporter also accepts chloride, hydroxyl ions (OH−), and oxalate as substrates. SLC26A2 is expressed at high levels in developing and mature cartilage, as well as being expressed in lung, placenta, colon, kidney, pancreas and testis.
RNA component of mitochondrial RNA processing endoribonuclease, also known as RMRP, is a human gene.
Winchester syndrome is a rare hereditary connective tissue disease described in 1969, of which the main characteristics are short stature, marked contractures of joints, opacities in the cornea, coarse facial features, dissolution of the carpal and tarsal bones, and osteoporosis. Winchester syndrome was once considered to be related to a similar condition, multicentric osteolysis, nodulosis, and arthropathy (MONA). However, it was discovered that the two are caused by mutations found in different genes; however they mostly produce the same phenotype or clinical picture. Appearances resemble rheumatoid arthritis. Increased uronic acid is demonstrated in cultured fibroblasts from the skin and to a lesser degree in both parents. Despite initial tests not showing increased mucopolysaccharide excretion, the disease was regarded as a mucopolysaccharidosis. Winchester syndrome is thought to be inherited as an autosomal recessive trait.
Boomerang dysplasia is a lethal form of osteochondrodysplasia known for a characteristic congenital feature in which bones of the arms and legs are malformed into the shape of a boomerang. Death usually occurs in early infancy due to complications arising from overwhelming systemic bone malformations.
Parastremmatic dwarfism is a rare bone disease that features severe dwarfism, thoracic kyphosis, a distortion and twisting of the limbs, contractures of the large joints, malformations of the vertebrae and pelvis, and incontinence. The disease was first reported in 1970 by Leonard Langer and associates; they used the term parastremmatic from the Greek parastremma, or distorted limbs, to describe it. On X-rays, the disease is distinguished by a "flocky" or lace-like appearance to the bones. The disease is congenital, which means it is apparent at birth. It is caused by a mutation in the TRPV4 gene, located on chromosome 12 in humans. The disease is inherited in an autosomal dominant manner.
Kenny-Caffey syndrome type 2 (KCS2) is an extremely rare autosomal dominant genetic condition characterized by dwarfism, hypermetropia, microphthalmia, and skeletal abnormalities. This subtype of Kenny-Caffey syndrome is caused by a heterozygous mutation in the FAM111A gene (615292) on chromosome 11q12.
Family with sequence similarity 111 member A is a protein that in humans is encoded by the FAM111A gene.
Cousin syndrome is a genetic condition characterized by short stature at birth, a short neck with low-positioned external ears, as well as congenital malformations of the skeletal system affecting the shoulders, the pelvis, the neck, and the limbs. The condition determines physical disability, particularly affecting deambulation, and hearing loss while intelligence is not affected.
Schneckenbecken dysplasia is a rare pre-natally fatal hereditary autosomal recessive condition which affects the bones and pre-natal growth.
Progressive pseudorheumatoid disyplasia, also known as progressive pseudorheumatoid arthropathy of childhood (PPAD), is a disorder of bone and cartilage that affects many joints. The disorder leads to stiff joints, short stature and widening of the ends of the finger and toe bones as well as other tubular bones.
